Cost, liability concerns delay pond cleanup proposal for a year

Published: January 15, 2009

HOLLIS - For almost two decades, the town has been eyeing a cleanup of Flint Pond, but it will take at least another year before officials make a decision, put together a warrant article and ask voters at town meeting to support it.
That's because the proposed cleanup raises a number of concerns ranging from cost and liability to environmental impact.
On Monday, Bruce Moran, representing the Flint Pond Improvement Association, and representatives of the state Department of Environmental Services proposed a cleanup of a 1- or 2-acre portion of the 50-acre body of water.
The residents' group is seeking town approval and the release of $128,114, plus interest, set aside in a town reserve fund for the cleanup.
The residents' group has committed roughly $10,000 for the state application needed before the project is started.
The town has asked the association to do more research on the project and come back next year.
At issue is the existence of arsenic on the bottom of the pond. Arsenic is a heavy metal that is toxic in high concentrations.
Some observers have speculated that the metal leached into the pond from ground water or from logs treated with a chemical containing arsenic and disposed in the pond after the hurricane of 1938.
Cleaning up the pond would require hydro-raking, a type of underwater raking to pull up plant material without disturbing the pond's bottom.
Plant material would be loaded on a barge, dragged to shore and left out to dry.
Nine years ago, after studying the pond, the Army Corps of Engineers estimated that it would cost the town $9 million to dredge the entire, 50-acre pond.
Selectmen nixed the project.
Meanwhile, residents of Flint Pond have continued to complain about weeds and "floating islands" of debris that have kept them from enjoying swimming, fishing and water sports on the pond.
The pond is also plagued by milfoil, a prolific, non-native, aquatic plant.
Dredging to remove milfoil roots, moreover, poses another problem: the process would disturb arsenic in sediment, according to experts.
Added to that are concerns about the location of the pond, over an aquifer, and the fact that the pond is spring fed and can't be drained.
State DES officials, who support the cleanup, told officials that the materials dredged would not pose a risk to the environment if they are dried and contained appropriately.
The state is recommending that the materials removed be deposited in the town's stump dump, placed over an impermeable cover, and covered with dirt.
Should the arsenic leak into the ground, however, the state would not be held liable, the DES representatives said.
State Rep. Dick Drisko, chairman of a legislative weeds study committee, said the town has few, if any, options to control the weeds.
"We're basically out of solutions," Drisko said.

This article appears in the January 2 2009 issue of New Hampshire Business Review